Structure of importin-β bound to the IBB domain of importin-α

@article{Cingolani1999StructureOI,
  title={Structure of importin-$\beta$ bound to the IBB domain of importin-$\alpha$},
  author={Gino Cingolani and Carlo Petosa and Karsten Weis and Christoph W. M{\"u}ller},
  journal={Nature},
  year={1999},
  volume={399},
  pages={221-229}
}
Cytosolic proteins bearing a classical nuclear localization signal enter the nucleus bound to a heterodimer of importin-α and importin-β (also called karyopherin-α and -β). The formation of this heterodimer involves the importin-β-binding (IBB) domain of importin-α, a highly basic amino-terminal region of roughly 40 amino-acid residues. Here we report the crystal structure of human importin-β bound to the IBB domain of importin-α, determined at 2.5 Å and 2.3 Å resolution in two crystal forms… 
The Auto-inhibitory Function of Importin α Is Essentialin Vivo *
TLDR
A model where the auto-inhibitory activity of importin α is required for NLS-cargo release and the subsequent Cse1p-dependent recycling of Importin α to the cytoplasm is proposed.
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TLDR
It is proposed that by controlling the degree of strain in the tertiary structure of importin β, the IBB domain modulates the affinity of the import complex for nucleoporins, thus dictating its persistence inside the NPC.
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TLDR
This work reports the identification of a second nucleoporin binding region in the NH2-terminal half of importin β, which is important for its nuclear import function.
Biophysical Characterization of Interactions Involving Importin-α during Nuclear Import*
TLDR
The results support the model of regulation of nuclear import mediated by the intrasteric autoregulatory sequence of importin-α and provide a quantitative description of the binding and regulatory steps during nuclear import.
Molecular Basis for the Recognition of Snurportin 1 by Importin β*
TLDR
It is proposed that in vivo the synergy of Nup153 and nuclear RanGTP promotes translocation of uridine-rich ribonucleoproteins into the nucleus.
Biochemical propensity mapping for structural and functional anatomy of importin α IBB domain
TLDR
This study distinguished the location and properties of amino acids important for each function of the importin α I BB domain by mapping the biochemical/physicochemical propensities of evolutionarily conserved amino acids of the IBB domain onto the structure associated with each function.
Biochemical propensity mapping for structural and functional anatomy of importin α IBB domain
TLDR
This study distinguished the location and propensities of amino acids important for each function of the importin α IBB domain by mapping the biochemical/physicochemical propensity of evolutionarily conserved amino acids of the I BB domain onto the structure associated with each function.
Crystal Structure of Rice Importin-α and Structural Basis of Its Interaction with Plant-Specific Nuclear Localization Signals[W]
TLDR
The results reveal the molecular basis of a number of features of the classical nuclear transport pathway specific to plants, including two NLSs, previously described as plant specific, that bind to and are functional with plant, mammalian, and yeast importin-α proteins but interact with rice import in-α more strongly.
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